1. Field of the Invention
The present invention relates to a transfer controlling method and transfer controlling apparatus for controlling transfer of image data, and a storage medium storing a program.
2. Description of the Related Art
In some cases, an image reading apparatus having an image reading function, such as a scanner or digital camera, optically reads an image, and transfers the image data to an information processing apparatus such as a PC, tablet PC, smartphone, or Web server. In this case, methods for transferring image data to the information processing apparatus are roughly classified into a non-compression transfer method and a compression transfer method. The non-compression transfer method is a transfer method of directly transferring image data read by the image reading apparatus as uncompressed data without compressing the image data. In contrast, the compression transfer method is a method of compressing image data by JPEG encoding or the like by the image reading apparatus and then transferring the compressed image data. Japanese Patent Laid-Open No. 2005-215954 describes that a data compression method at the time of forming an image is decided based on the type of interface and image forming conditions.
The non-compression transfer method has an advantage in which high-quality image data free from degradation of image data is transferred to the information processing apparatus, and when the information processing apparatus performs image processing or the like after transfer, a high-precision processing result can be easily obtained. To the contrary, the non-compression transfer method has a disadvantage in which the data amount is large, and the traffic load, the CPU load, or the I/O load on a disk such as a hard disk or SSD in a transfer destination device becomes large.
In contrast, the compression transfer method has an advantage in which the data amount is small, and the traffic load, the CPU load, or the I/O load on a disk can be suppressed. However, the information processing apparatus performs image processing or the like on a degraded image, and it is difficult to obtain a high-precision result. For example, if the information processing apparatus performs character recognition or the like on image data JPEG-encoded by the image reading apparatus, image recognition readily fails because mosquito noise exists at a character portion owing to JPEG encoding. In this manner, the non-compression transfer method and the compression transfer method have a tradeoff relationship.
In Japanese Patent Laid-Open No. 2005-215954, a data compression method at the time of transferring an image is decided based on the type of interface at the time of transferring an image, and image processing to be executed in the apparatus itself that transfers an image. However, image processing to be executed on image data at the transfer destination of the image data is not taken into account. Hence, the image data may be transferred in a data format not suited to image processing at the transfer destination. For example, processing of recognizing a character in scanned image data and rotating the orientation of the image is sometimes performed as image processing to be executed at the transfer destination. In this image processing, the character portion is recognized from the scanned image data, and the entire image data is rotated in accordance with the orientation of the character. If the image reading apparatus compresses the image data by JPEG encoding or the like, the character portion is degraded, and the character recognition cannot be performed at high precision, resulting in a poor image processing precision.
If the non-compression transfer method is selected without exception in consideration of the fact that no proper image processing result is obtained, the traffic load, the CPU load, and the I/O load on a disk such as a hard disk or SSD in the transfer destination device are increased. It is very hard for the user to uniquely decide the non-compression transfer method or the compression transfer method while considering the tradeoff between a decrease in the precision of image processing or the like by the compression transfer method, and the traffic load, CPU load, and I/O load by the non-compression transfer method.